Overview
- The peer‑reviewed county analysis, published Tuesday, March 24 in the American Journal of Preventive Cardiology, examined 2000–2020 data across 819 U.S. locations representing about 80% of adults 25 and older.
- Researchers identified a lopsided U‑shaped pattern with the lowest cardiovascular mortality near 23°C (74°F), and risk rose more steeply as temperatures moved colder than that point.
- Cold was linked to about 6.3% of all cardiovascular deaths each year compared with about 0.33% for heat, based on more than 14 million recorded deaths.
- The team said cold triggers blood vessel tightening, inflammation, and pro‑clotting changes that raise the odds of heart attacks and strokes, especially in older adults and people with chronic diseases.
- Authors urged hospitals and EMS to plan for surges during cold periods and noted limits from monthly, population‑level data, with a follow‑up planned to test daily temperature effects and EMS activations and a presentation scheduled at ACC.26 on March 30.